The Center has provision for the use of its resources for pilot and feasibility experiments to be carried out without the need for the request to be reviewed by the Scientific Advisory Committee. These experiments are usually of short duration and carried out for the purpose of obtaining a very limited set of data. These resources are allocated at the discretion of the Director. The NMR Center has assisted several groups in this regard: (i) obtain high resolution MR images of the rat brain for the purpose of preparing an atlas of the rat brain for use with PET data, (ii) obtain high-resolution MR images of an isolated human heart specimen for modeling biomechanics of the heart, (iii) obtain high-resolution MR images of a fixed human brain, (iv) obtain additional data on cerebral perfusion maps of a rat model with subarachnoid hemorrhage to complete a study that was carried out the previous year, and (v) obtain apparent diffusion coefficient (ADC) maps and perfusion maps of the rat brain in a photothrobolytic stroke model. Allocation of a limited amount of NMR Center's time on the scanners in a timely manner serves a very useful purpose of providing the investigators data which are sometimes required with minimal delay. In the past, a number of investigators have used this Director's discretionary time for obtaining pilot data for applying for grant support, for carrying out feasibility studies which were used in designing new experiments that were subsequently carried out in the NMR Center as regular projects, and for tying up loose ends of previosly carried out experiments in the Center.